The best digital delay, IMO, is the line 6 dl4. It's got a ton of options, including 15 different delays, three presets, tap tempo, and a looper. There are several on craigslist and ebay for around $150. I know its a little more than your budget but I think any pedal is expensive if you're only going to use it for one song. EHX also makes the deluxe memory boy. Analog with a tap tempo. Seen them used from $110 to $135. All that being said, it's up to you. Just my two cents.
I'm a pedal moron, what is a tap tempo?